Search results for "Fish"
showing 10 items of 3164 documents
Controlling of geosmin and 2‐methylisoborneol induced off‐flavours in recirculating aquaculture system farmed fish—A review
2018
Towards interpretable classifiers with blind signal separation
2012
Blind signal separation (BSS) is a powerful tool to open-up complex signals into component sources that are often interpretable. However, BSS methods are generally unsupervised, therefore the assignment of class membership from the elements of the mixing matrix may be sub-optimal. This paper proposes a three-stage approach using Fisher information metric to define a natural metric for the data, from which a Euclidean approximation can then be used to drive BSS. Results with synthetic data models of real-world high-dimensional data show that the classification accuracy of the method is good for challenging problems, while retaining interpretability.
The effect of Shallow Tillage on soil erosion in a semi-arid vineyard
2019
Soil erosion has been considered a threat for semi-arid lands due to the removal of solid materials by water and wind. Although water erosion is currently considered the most important process of soil degradation, a growing interest has been drawn to the impact of soil tillage. Although numerous studies on tillage erosion have been carried out on arable land using a moldboard plow, a chisel, and a tandem disc for different crops, there are no studies on the effect of shallow tillage on soil redistribution in vineyards. The aim of this work was to evaluate the soil tillage erosion rate in a vineyard using a 13C natural abundance tracer. A strip of soil (C3-C soil) was removed, mixed with C4-…
Soil interpretation in the context of anthropedogenic transformations and pedotechniques application
2018
Abstract Following a long and vigorous study carried out by the International Committee on Anthropogenic Soils (ICOMANTH), the Soil Taxonomy (ST) classification system recently incorporated a number of changes to include Human-Altered and Human-Transported soils, generally called anthropogenic soils. These changes underwent careful scrutiny as they affect the current classification of existing soil series, and as the proposals and logics are as yet untested against existing data and descriptions. Particular attention was given to the diagnostic characteristics of the anthropogenic soils and to the Subgroups for Human-Altered and Human-Transported soils. In this study, we consider a frequent…
Effects of tilling methods on soil penetration resistance, organic carbon and water stable aggregates in a vineyard of semiarid Mediterranean environ…
2018
Tillage, especially in semiarid Mediterranean environment, enhances the mineralization process of soil organic matter (SOM) and, in turn, decreases aggregate stability. Furthermore, continuous tillage leads to the formation of plough pan beneath the tilled layer. In the present study, we investigated the effect of an innovative self-propelled machine (spading machine, SM) for shallow tillage on SOM, water stable aggregates (WSA) and soil penetration resistance (PR). Such effects were compared to those of chisel plough (CP), rotary tiller (RT) and no tillage (NT). Each tilling method was applied up to a depth of 15 cm, whereas in NT only a brush cutter was used for weed control. Soil analyse…
The impact of the age of vines on soil hydraulic conductivity in vineyards in eastern Spain
2017
Soil infiltration processes manage runoff generation, which in turn affects soil erosion. There is limited information on infiltration rates. In this study, the impact of vine age on soil bulk density (BD) and hydraulic conductivity (Ks) was assessed on a loam soil tilled by chisel plough. Soil sampling was conducted in the inter row area of six vineyards, which differed by the age from planting: 0 (Age 0; just planted), 1, 3, 6, 13, and 25 years (Age 1, Age 3, Age 6, Age 13, and Age 25, respectively). The One Ponding Depth (OPD) approach was applied to ring infiltration data to estimate soil Ks with an α* parameter equal to 0.012 mm-1. Soil bulk density for Age 0 was about 1.5 times greate…
El marcaje revela un intercambio limitado de inmaduros de tortuga boba (Caretta caretta) entre regiones en el Mediterráneo occidental
2008
El marcaje revela un intercambio limitado de inmaduros de tortuga boba (Caretta caretta) entre regiones en el Mediterráneo occidental. – Se investigó el intercambio de inmaduros de tortuga boba (Caretta caretta) entre las regiones septentrional y meridional del Mediterráneo occidental a partir de los datos obtenidos por varios programas españoles de marcaje. El rango de la longitud recta de caparazón de las tortugas marcadas fue de 23 a 74 cm. 36 de ellas se recapturaron tras un intervalo medio de 390,5±462,6 días (DS). Como la distancia media de dispersión (MDD) de una población de tortugas que se dispersan por el Mediterráneo occidental se estabilizaría al cabo de 117 días (IC 95%: 98-149…
A microcosm experiment to evaluate the influence of location and quality of plant residues on residue decomposition and genetic structure of soil mic…
2007
The effects of location (soil surface vs. incorporated in soil) and nature of plant residues on degradation processes and indigenous microbial communities were studied by means of soil microcosms incubation in which the different soil zones influenced by decomposition i.e. residues, soil adjacent to residues (detritusphere) and distant soil unaffected by decomposition (bulk soil) were considered. Plant material decomposition, organic carbon assimilation by the soil microbial biomass and soil inorganic N dynamics were studied with 13 C labelled wheat straw and young rye. The genetic structure of the community in each soil zone were compared between residue locations and type by applying B- a…
Length-Weight Relationships of 52 Species from the South of Sicily (Central Mediterranean Sea)
2022
The Length-Weight relationships (LWRs) of 52 species (14 never reported before) of fishes, crustaceans and cephalopods living on the shelf and upper slope off Southern Sicily are provided. Data were collected in the framework of the International bottom trawl survey in the Mediterranean (MEDITS) in the South of Sicily (Central Mediterranean), covering a time frame ranging from 2012 to 2019. Linear regressions were significant for all species (p < 0.05) with R2 values ranging from 0.86 to 0.99. The intercept (a) of LWRs ranged from 0.0003 to 0.4677, while the slope (b) ranged from 2.1281 to 3.306. The Welch t-test, used to evaluate differences between the obtained LWRs with those reported…
The use of energy in the Mediterranean fishing catching sector. A Sicilian perspective
2010
This article address an issue of paramount importance in the Mediterranean area, that is the efficient use of energy and sustainability of fishing sector. A recent study concerning the situation of Fishery and Aquaculture in Sicily highlighted that the Sicilian fishing system requires a bigger amount of energy than the typical Italian or European situation, in order of getting the product available to the market. On the other hand this involves an higher level of environmental pollution, for a given quantity of catch. One of the main findings is that there is a need for a clear, scientifically-founded panorama of the situation and that further studies should be undertaken to provide fishing…